All you need to know about Vitamin A: benefits, dangers, foods

Visit vitamin A was the first vitamin to be discovered, in 1913, hence the letter it carries.

Note: this article is one of the chapters in the Blooness feeding guidea guide to the ingredients of the ideal diet for humankind.

It is a fat-soluble vitamin, in the sense that it is soluble in fats, and therefore stored in them, as we learned in the previous chapter.

It is stored in large quantities by the body, and is found either in its natural form or as provitamin A. Pro, meaning "precursor" of vitamin A. The main provitamin A is beta-carotene, found in carrots, but also in certain fruits and vegetables. vegetables.

Benefits of vitamin A

Vitamin A and vision

Vitamin A plays an indispensable role in the quality of vision, helping to trigger nerve impulses in the optic nerves. Insufficient vitamin A intake can therefore increase the risk of cataracts and macular degeneration.

Antioxidant properties of beta-carotene

Antioxidants help combat cellular aging and oxidative stress. Beta-carotene, a precursor of vitamin A, has important antioxidant properties.

Vitamin A and skin health

Vitamin A is a precursor of the melanin responsible for skin pigmentation. A good intake of vitamin A and beta carotene helps prepare the skin for the sun, protect skin cells against external aggression and promote cell renewal.

Finally, vitamin A is said to have beneficial properties for bone growth, mucous membrane and hair health.

Deficiencies and excesses

Vitamin A deficiency is virtually non-existent in developed countries. They are most common in disadvantaged populations, and mainly lead to impaired vision and reduced immunity.

A priori, there's no reason to take vitamin A supplements.

In high doses, beta-carotene intake can lead to orange-colored skin, known as carotenoderma. Finally, in pregnant women, an excess of vitamin A can lead to foetal malformations.

As a result, vitamin A intake from food is more than sufficient to cover our needs.

Recommended dose of vitamin A

The Recommended Dietary Allowance (RDA) for vitamin A is around 700 to 900 µg per day, or 0.8mg / day.

Foods rich in vitamin A

Vitamin A is found in foods of animal origin: butter, eggs, milk, cheese, organ meats, liver, etc.
Provitamin A, and in particular beta-carotene, is found in fruits and vegetables: carrots, apricots, mangoes, red peppers, lettuce, parsley, spinach, dark-green leafy vegetables, cruciferous vegetables, sweet potatoes and so on.

Please note that lipids have a beneficial effect on vitamin A absorption.

Conclusions on vitamin A

Vitamin A is found naturally in the foods recommended in this guide, including eggs, butter, organ meats and green vegetables. It is also easily synthesized via pro-vitamin A, which is abundant in fruit and vegetables in general.

So, a priori, there's no reason to supplement, whatever type of diet you choose, especially as over-dosing is largely inadvisable. So don't forget to check the multi-vitamin you may be buying.